Arches, i. 19; subordination of, 48; ii. 75, 78, 303, 305; semicircular or segmental, i. 49, 244; in rims or orders, 224; of windows, their filling in, 253; suggest a higher pitch of roof than trabeated construction, 255; as to form, 354; to windows in Anglo-Saxon work, ii. 37; in form rather than construction, 52; most obvious form of, 73, 178; development of, 74, 136; decoration by mouldings, etc., 76, 120, 139, 141; orders of, 76, 78, 86, 142, 143, 146, 151; semicircular, 178, 179; semi-elliptical, 179; introduced by the Romans into their architecture, 303, 305. Architects, English, duties of, i. 352; Royal Institute of British, 364; ii. 66; to direct their primary attention to the study of English architecture, 3; past history of our art essential to, 295. Architecture, love for, i. 1; native, 2; study of, 2, 16; ii. 295, 322-326; latest original style of, i. 6; of the Western Empire, 12; of the Eastern Empire, ii. 4, 6, 7; new phase of, under Rollo, i. 44; purely arcuated, 47; secular, of Italian cities, 206; rationale of, 271; conditions to be demanded of our future, 273; unites all arts in one, 340; necessity to master the whole range of, 341; development in, 361; early, in Great Britain, ii. i; French, 2; English, 3; two great divisions of mediæval, 5; Anglo-Saxon, 36; early Norman, 58; at the close of the 11th century, 134; differs in its origin from the sister arts of sculpture and painting, 291; definition of, as distinguished from mere building, 292; history of, reserved for our own age, 293. Architraves, i. 46, 227. Archivolts, transitional, i. 124. Arcs doubleaux, i. 56; ii. 182. Arcs ogives, or diagonal ribs, ii. 182. Arcuated architecture, i. 18, 47, 72, 274; ii. 5; system of, 6, 73, 136, 138, 303, 306, 308. Ardoilen, island of, ii. 20. Argos, ii. 300. Arles, cloisters at St. Trophimus, i. 99, 229. Arnolpho, architect of the cathedral at Florence, ii. 279, 280. Arran, island of, ii. 15. Arris vaulting, of the Roman and Romanesque builders, i. 238; substitution of the rib for, 239. Art, its growth, i. 4, 143; primitive, 5; under the later Pagan emperors, 10; study of, 27; its reawakening in the 10th century, 38; ancient, 142; decoration, ii. 60; of architecture, 61. Art workmen, i. 25. Arthur, King, ii. 14. Artists, training as, i. 339; ii. 325. Assisi, church of St. Francis at, i. 134. Assyria, art of, i. 5, 13; ii. 298. Assyrian sculptures, ii. 230; structures, 304. Athelstan, ii. 59. Athelwold, Bishop of Winchester, ii. 33, 104. Athens, churches at, ii. 257; St. Nicodemus at, 258. Atreus, treasury of, or the tomb of Agamemnon at Mycenæ, ii. 300. Atridæ, days of the, ii. 300. Attic base, i. 150. Augustan age, i. 10, 142. Augustine, St., ii. 26, 32, 58; founder of the church of St. Martin, Canterbury, 27, 65. Augustus, reign of, ii. 231. Aungre, ii. 55.